RX – SAQ

SAQ 17.2 kHz Alexanderson Sweden

With many thanks, a large portion of this page content was taken from the webpage of Bob G4PVB, one of our members at VARC.

The Alexanderson Alternator

SAQ is situated in Grimton, Sweden and is the last transmitter in the world generating rf power without any electronic parts. No tubes, no semiconductors, only an engine driving an AC generator. Grimeton Radio (SAQ) broadcasts on 17.2 kHz and is a recognised world heritage site. For more detailed information about SAQ you can visit their own website which can be found HERE!

Grimeton (call sign SK6SAQ) still transmits a message to the world twice a year:
On Alexanderson Day, Christmas Eve and at other times during the year the only workable Alexanderson alternator transmitter in the world is used to transmit short Morse messages on 17.2 kHz using a 1.9 km (1.2 mile) horizontal wire antenna which should be easily receivable all of Europe. The transmitter is preserved as a historical remenant of early radio technology and as an example of VLF (Very Low Frequency) equipment.

Alexanderson Day commemorates its inventor Ernst Fredrik Werner Alexanderson, a Swedish engineer. The Alexanderson day transmissions are held either on the last Sunday in June, or on the first Sunday in July, whichever comes closer to 2 July. On this day they have an ‘open house’ at the Swedish government VLF transmitter site where visitors can see the alternator in action.

These transmissions cannot be received by ordinary radios because of their low frequency. Modern enthusiasts often monitor the transmissions using a PC with antenna connected to the soundcard input and appropriate free software (see below) or a short-wave receiver with an upconverter or any of several receivers designed to receive VLF transmissions directly. In recent years, Software-defined radio receivers have proven to be very useful and effective in receiving transmissions from SAQ around the world.

Also, SK6SAQ may make test transmissions about 14:00 UTC the day before published broadcast.

Free SAQrx VLF radio receiver software to Rx SAQ on your PC:

To download the latest SAQrx VLF radio receiver software v0.98 you can click the link HERE!. It will likely go straight to your Downloads folder.

Connect a simple Long Wire antenna (I’m using 20 metres insulated wire 5 metres high) down the garden to the microphone or line-in input to a redundant PC as excess static may damage the soundcard.

2 X 1N5406 diodes back to back and as kindly advised by Norman G8ATO of Verulam ARC a 100k Ohm resistor across the PC input as in image below enhances protection. Also, his recommendation of the 4.7nF capactor which serves as a filter. Ground using e.g. large crocodile clip via central heating copper water pipe. All components available from eBay but often sold in bulk so club together to keep cost down e.g. 1N5406 diodes £2 for ten.

I have been advised that my static protector circuit may be inadequate. (Comments welcome.) So along with the previous circuit I’m using a 2uF isolating capacitor and a mains neon indicator bulb, without the usual series limiting resistor, wired across the aerial input in parallel and in front of the back to back diodes. As advised by Marc Bruno IK1ODO: “…small neon pilot lamp (without resistor). The neon lamp is used as transient limiter, lighting when the DC voltage in antenna exceeds 120V or so. The lamp lights often during thunderstorms – be careful, high wires may be dangerous !

To test the neon indicator before installing it in the protector circuit I used 240 Volts with a 220kΩ inline series resistor for a medium glow.

Above circuit diagram installed in a project box.

If you live in a strong MW RF field then that could cause the neon to glow if fed with a long wire

I have also installed a 1M Ohm leakage path resistor at the front end of the circuit.

Before turning on ensure all levels are LOW (you may need to attenuate the antenna signal) and be especially careful of overload if wearing headphones.

Listen to SAQ https://alexander.n.se/en/the-radio-station-saq-grimeton/lyssna-pa-saq/

Laptop is even better because you can transport it to an EMC quiet zone whilst away e.g. on holiday using internal battery not inteference inducing mains power. Also, consider to use onboard Windows Sound Recorder so that you may decode the transmission at your leisure either by ear or Morse reading software. Use the SAQrx VLF Radio to listen to the broadcast below:


SDR Receivers
There are only a few SDR receivers that are capable of receiving signals on such low frequencies, one being at the univercity of Twente in the Netherlands which can be found HERE!

To listen to SK6SAQ on the SDR, do like this:
Frequency enter 17.2 kHz
Waterfall view ‘max in’
Bandwidth ‘CW narrow’
Check frequency 17.2 kHz

Good luck!

73 Bob G4PVB

If you require an audio interface from RX to PC then here is my effort: http://g4pvb.eu5.net/psk31.htm

Here is my copy from SAQ taken on Wednesday 24th October 2018:
SAQ Sweden RST 337

16:43 UTC TUNE UP STARTED:

||: VVV VVV VVV DE SAQ SAQ SAQ :||
17:00 UTC MESSAGE STARTED:
CQ CQ CQ DE SAQ SAQ SAQ = THIS IS GRIMETON RADIO/SAQ IN A TRANSMISSION USING THE ALEXANDERSON 100 KW ALTERNATOR ON VLF 17.2 KHZ = THE ATLANTIC TELEGRAPH LINE WAS OPENED IN 1866 II II II II 1866 BETWEEN IRELAND AND NEW FOUNDLAND THUS CONNECTING THE TWO CONTINENTS. TODAY WE PAY TRIBUTE TO COMMUNICATION BETWEEN PEOPLE, IN A WORK FOR BUILDING PEACE. = NB IME WE NEITHER REQUEST QSL REPORTS ON THIS TRANSMISSION, NOR WILL RESPOND WITH QSL = CARDS = SIGNED OS WORLD HERITAGE GRIMETON RADIO STATION AND THE ALEK II II II II ALEXANDER = GRIMETON VETERAN RADIOS VAENNER ASSOCIATION = AR QRU DE SAQ ST II II SAQ SAQ SAQ VA
17:06 UTC END

END OF FILE

With many thanks to Bob G4PVB for use of content from his website which can be found HERE!

Secured By miniOrange